I. Field of the Invention
The present invention relates to a vector display apparatus for displaying a vector which represents a feature or features of information to be processed such as an image (e.g., a character or any other figure), various kinds of speech inputs, and technical information to be retrieved.
II. Description of the Prior Art
In order to discriminate information such as an image (e.g., a character and any other figure), various kinds of speech inputs, and technical information to be retrieved, there is known a method of discriminating the information as a vector comprising a single component or a plurality of components.
For example, when the information is an image, the image pattern which has been formed by printing or the like and is subjected to image recognition is mapped by an optical lens on the light-receiving surface of an image sensor comprising a CCD or a MOS sensor. A multi-value digital signal as image information is output from the image sensor and is binarized with a proper threshold value (if a plurality of threshold values are used, a multi-value conversion different from that described above is performed). The binarized signal is stored in a memory. As occasion demands, the binarized image information is subjected to preprocessing for shaping the image before being stored in the above or another memory. The preprocessing includes noise reduction and normalization for position, size, inclination and width.
A feature extraction from the image information stored in the memory is taken place in a projection-processing section.
In order to project an image on a given axis (e.g., the X-axis), the memory which stores the image information is scanned in a direction (e.g., the Y-axis) having a predetermined relationship with the given axis, and the image information is read out serially or parallelly in time. The readout image information is transferred to the projection-processing section, in which pieces of the transferred image information are sequentially accumulated. Accumulated values sequentially obtained by such accumulations are stored at predetermined positions corresponding to the given axis in the above or still another memory.
In order to digitally process the projection features described above, the accumulated values as input data are regarded as a component of vector. One or a plurality of intensity distributions is dealt as a vector having a large number of components. Therefore, if the accumulated values for an intensity distribution are stored at addresses 1 to n, this intensity distribution constitutes an n-dimensional vector.
In this case, in order to increase the image recognition rate, projection processing must be performed for the same image information on a large number of axes to extract different types of features. Therefore, an image to be recognized is dealt as a set of a large number of multi-dimensional vectors.
Each of the multi-dimensional vectors is represented such that a pair of values represent the order and the magnitude of the vector. The pair of order and magnitude are digitally processed in units of bytes. In digital processing, intermediates states represented by vector components need not be displayed.
In order to discriminate an optical pattern displayed, an image reading apparatus utilizing an optical technique (OCR processing) has been used in practice. In such an image reading apparatus, features of the optical pattern displayed are extracted by projections, and the projection features extracted are compared with those of reference patterns for classification. The image classified in such a manner is correlated with a large number of images belonging to the given class by correlation calculations to specify the image, i.e., to recognize the image. In the correlation calculations, the projection features of the input image to be recognized are compared with those of a large number of image recognition reference patterns, which are ordered according to the degree of similarity of each of them to the input image so as to specify the latter according to the above ordering.
In conventional vector calculation techniques, since only digital techniques are used, intermediate results need not be displayed to the outside of calculators. The present invention is made to provide an optical input device for a processing unit compatible with optical processing rather than digital processing.
In general, the magnitude of a vector is numerically displayed by a combination of values representing vector components and values each representing the intensity of the vector component. When these values are directly given on a display for an input device of an optically processing unit, numerical values to be input must be appreciated for optical processing. As a result, the reading unit in such a processing unit becomes complicated and bulky.
In addition, when vector components are numerically given on a display, a large number of vector components cannot be displayed at the same time.